Impatiens necrotic spot virus

Impatiens necrotic spot virus (INSV) is a plant pathogenic virus of the order Bunyavirales. It was originally believed to be another strain of Tomato spotted wilt virus but genetic investigations revealed them to be separate viruses. It is a single stranded RNA It has a tripartite genome and is largely spread by the insect vector of the western flower thrips. The virus infects more than 648 species of plant including important horticultural and agricultural species such as fuchsia, tomato, orchids, and lettuce (especially romaine). As the name implies, the main symptom on plants is necrotic spots that appear on the leaves. The INSV virus infects by injecting the RNA the virus contains into the cell which then starts using the cell resources to transcribe what the virus RNA states. Viral infection can often result in the death of the plant. The disease is mainly controlled by the elimination of the western flower thrip vector and by destroying any infected plant material. Impatiens necrotic spot virus (INSV) is a plant pathogenic virus of the order Bunyavirales. It was originally believed to be another strain of Tomato spotted wilt virus but genetic investigations revealed them to be separate viruses. It is a single stranded RNA It has a tripartite genome and is largely spread by the insect vector of the western flower thrips. The virus infects more than 648 species of plant including important horticultural and agricultural species such as fuchsia, tomato, orchids, and lettuce (especially romaine). As the name implies, the main symptom on plants is necrotic spots that appear on the leaves. The INSV virus infects by injecting the RNA the virus contains into the cell which then starts using the cell resources to transcribe what the virus RNA states. Viral infection can often result in the death of the plant. The disease is mainly controlled by the elimination of the western flower thrip vector and by destroying any infected plant material. The disease is an ssRNA that injects itself into the host cell, then has the host cell duplicate the RNA sequence as well as the coat protein used to disguise the RNA. The infected cell also starts to create movement proteins that facilitate the movement of the virus through the plant making the plasmodesmata (connections between plant cells) large enough to allow the virus to move throughout the plant. The virus can then also infect other plants by either the infected sap or a vector, such as an insect, which will start the cycle over again. Typically the best way to manage a virus problem is to get rid of any vectors that may carry the disease. This easily can be done by an insecticide. Another acceptable method would be resistance plants. These plants would kill off any infected cells, not allowing the virus to spread. Furthermore, larger distance between plants could help the spread of the disease not allowing the virus to be transmitted virtually. This can be done by controlling weeds and thrips, the most common vector transmission. Chemical controls of herbicides and insecticides can be implemented and is the best form of control. If virus remains a problem, other plants can be planted in that area that do not have the traits required for infection of INSV. INSV has a wide host range and can be found in over 300 plant species including weeds, fruits, vegetables and ornamental crops. Of these, the most severely affected include tomatoes, lettuce, pepper and peppermint as well as most all ornamentals. Symptoms of infection include a downward curling of the leaves, leaf tip dieback, stunting, necrosis of growing leaf tips, sunken ‘chicken pox-like’ spots on leaves (often with a surrounding halo), stem death and yellowing. Since these symptoms are so generic, extreme caution must be taken when introducing new plants to your greenhouse. Infected plants can not be cured and not all hosts display visible symptoms Western Flower Thrips are extremely hard to remove from their host plants, as they often dig themselves deep into blossoms, buds and other areas hard to reach with insecticides. So, even if plants are sprayed regularly with insecticide, INSV and other insect vectored viruses can not always be ruled out when forming diagnosis.